<?php
$db=new PDO('mysql:host=localhost;','root','12qwas');
$r=$db->exec('create database if not exists db3');
$r=$db->exec('use db3');
$r=$db->exec('create table if not exists students(xh varchar(9) primary key,name varchar(50),age int default 0)');
var_dump($r);
$r=$db->exec("delete from students where xh='233110201'");
var_dump($r);
$db->exec('truncate table students');
$r=$db->exec("insert into students(xh,name,age) values('233110200','张三',18),('233110201','李四',20),('233110202','往往',21)");
var_dump($r);
$r=$db->exec("update students set name='张三丰' where xh='233110201'");
var_dump($r);

